The development of stored program control (SPC) switches in the 1960's made it possible for telecommunications service providers to introduce many new and sophisticated telecommunications services that have benefited both users and public switched telecommunications network (PSTN) service providers. One such service, the 800 service, which was described in an article by D.Sheinbein and R.P.Weber entitled "800 Service Using SPC Network Capability" that appeared in The Bell System Technical Journal, Vol. 61, pp. 1737-1744, 1982, allowed a customer to establish an area of the country from which he or she can receive calls without charge to the calling parties. The desirability of such "free calling" is evidenced by its pervasiveness. Specifically, the volume of 800 service calls has increased to the extent that its traffic has become a substantial percentage of all toll calls served by existing telephone switching systems.
Recently however, there has been an increasing interest and demand for alternative "free calling" telecommunications services. In response to this interest, telecommunications service providers have offered a service by which a calling party may complete free telephone calls, provided he or she agrees to listen to an audio advertisement presented telephonically. (See, for example, The New York Times, Oct, 28, 1997 and The Wall Street Journal, Oct. 29, 1997) The advertisement is delivered to the caller through his or her telephone via the PSTN, and the advertiser pays the bill for the telephone call.
Service providers, consumers, advertisers and network operators all desire additional, innovative free calling methods. Consequently, a continuing need exists for methods and apparatus which meet this need, and in particular ones that provide interactive multimedia advertisements and/or presentations to the caller.